Reduce to lowest terms: $- \dfrac{1}{9} \div \dfrac{3}{7} = {?}$
Dividing by a fraction is the same as multiplying by the reciprocal of the fraction. The reciprocal of $ \dfrac{3}{7}$ is $ \dfrac{7}{3}$ Therefore: $ - \dfrac{1}{9} \div \dfrac{3}{7} = - \dfrac{1}{9} \times \dfrac{7}{3} $ $ \phantom{- \dfrac{1}{9} \times \dfrac{7}{3}} = \dfrac{-1 \times 7}{9 \times 3} $ $ \phantom{- \dfrac{1}{9} \times \dfrac{7}{3}} = \dfrac{-7}{27} $